Fluid dispensing device

ABSTRACT

The invention pertains generally to an improved fluid dispensing device, particularly a dispensing device which employs at least one hemispherical domed cannister source of reactants and which uses a color-changing dispensing plastic tip to inform the end-user if the reactants are at a proper use temperature.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of patent application Ser.No. 16/685,344 filed on 15 Nov. 2019 which is a divisional applicationof patent application Ser. No. 16/295,318 filed on 26 Mar. 2019, nowU.S. Pat. No. 10,538,378, which is a divisional application of patentapplication Ser. No. 15/903,368 filed on 23 Feb. 2018, now U.S. Pat. No.10,351,334.

TECHNICAL FIELD

The invention described herein pertains generally to an improved fluiddispensing device, e.g., a one-component or two-component polyurethanefoam.

BACKGROUND OF THE INVENTION

The invention relates generally to a pressurized chemical dispensingapparatus, and more particularly to a hand-held apparatus particularlysuitable for use in dispensing two-component systems, more particularlyurethane foams, wherein the apparatus includes a dispensing assemblyinterconnected to the canister supplies. Optionally the apparatus iscontained within a kit which permits one-handed operation.

The use of urethane and similar expandable foams has increased over theyears for numerous applications. Urethane foams are well known as havingdesirable characteristics useful for many applications, such asinsulation, adhesives or sealants. Urethane foams are also well knownfor their compatibility with low cost blowing agents which allow suchfoams to be applied by way of pressurized containers as well as theirnatural adhesive qualities which allow such foams to bond excellently toany number of substrates. Typically, urethane foams are the reactionproduct of two individual components, one being an isocyanate and theother being a resin. These two individual components when reactedtogether under pressure, give the resultant foam various chemicalcompositions, each such composition having significant utility in aparticular application. Thus, urethane foams may be specially formulatedto provide a final foam which is rigid, semi-rigid or flexible.

Closed cell urethane foams have particular utility in building andstructural insulation while open cell urethane foams have particularutility in packaging or non-insulating purposes. Regardless of cellstructure, two-component urethane foams are typically formed by mixingthe two or more individual foam components together when the foamcomponents exit respective supply containers. Individual material supplytubes leading from each foam component container convey the foamcomponents to a foam dispensing apparatus, such as a nozzle.

There are numerous applications in which polyurethane foam is used at asite for any number of applications in addition to its traditional usein the building trades as a source of insulation. Recently polyurethanefoam has become used with increasing frequency as a sealant in thebuilding trades for sealing spaces between window and door frames andthe like and as an adhesive for glueing flooring and roof tiles and thelike. The polyurethane foam for such in-situ applications is typicallysupplied as a one-component froth foam or a two-component froth foam. Aone-component foam means that both the resin and isocyanate for the foamis supplied in a single pressurized container and dispensed from thecontainer through a valve or gun attached to the container. Atwo-component “froth” foam means that one component is supplied in onepressurized container, typically the “A” container (i.e., polymericisocyanate, fluorocarbons etc) while the resin is supplied in a secondpressurized container, typically the “B” container (i.e., polyols,catalyst, flame retardants etc.). Typically, two-component kits usepressurized cylinders which are connected by hoses to a dispensing gun.There are advantages and disadvantages to one-component andtwo-component foams. One of the advantages of the two-component systemis its relatively long shelf life resulting from the fact that thechemicals are not mixed until they encounter one-another in thedispensing gun.

One application for a hand-held, portable two-component polyurethanefroth foam kit exists in the mining industry. In the event of a fire ina shaft being tunneled, standard procedure is to extinguish the fire bysealing the shaft with a fire “door” and then pumping out from the shaftsealed by the door, the air in the shaft to extinguish the fire. It hasbeen found that polyurethane foam is excellent for sealing the bulkheador door to the tunnel. As already noted, the polyurethane foam has anadhesive characteristic and the foam can be formulated to provide arelatively quick tack free time with little permeability for gas escape.Surprisingly, the fire door is not adjacent an open flame, and whatevertemperature the gases exhausted from the shaft are, they are notsufficiently high in temperature to disintegrate the foam. Because ofits long shelf life, a two-component foam is ideal for this application.Standard procedure is to simply provide two-component kits at the shaftbeing tunneled to seal and secure the fire door or bulkhead to the shaftin the event of a fire.

Different packaging arrangements are used by different manufacturers.Many two-component kit packages use some form of tray with knock-outholes through which the hoses extend after the box is opened and thehoses attached to the cylinder's valved fitting. However, there is atleast one two-component polyurethane froth foam box which utilizescylinders equipped with “dip tubes” which extend through the outletvalve from the inside bottom of the cylinder. This allows the cylindersto be placed upright in the box instead of upside down. This carton doesnot use a tray and has the hoses extend out the side of the box throughknock-out plugs. The carton is carried by a strap affixed to the topcover. The top cover is a flap which has to be opened and closed to gainaccess to the cylinder's valve after the hoses are connected to thecylinders.

What has been missing from the Prior Art however, is a foam dispensingdevice which couples both fail-safe operation by a two-stage activationprocedure, coupled with a dispensing mechanism whereby the dispensingmeans: is biased into a closed position; is actuated by rotationalmovement about a cannister longitudinal axis; has an extendable nozzleextension; and has a means for preventing hose deformation/crimpingduring shipment.

SUMMARY OF THE INVENTION

The invention is directed to an easily assembled foam dispensingapparatus in which two foam component supply containers are held inplace by an carrier assembly which includes a dispensing triggerassembly which is separate from the carrier assembly.

In one aspect of the Prior Art as illustrated in FIGS. 1-7, the entiredispensing apparatus and carrier unit is contained in a carrying case.The carrying case contains two foam component supply canisters and anactuating assembly in the form of two foam component supply tubes, eachhaving a predefined length which is sufficient to permit a dispensingassembly attached to the supply tubes to be operated remotely from thecarrying case while interconnected thereto. The material supply tubes,dispensing assembly and one or more detachable dispensing nozzles arepositioned within a designated area within the carrying case so that theapparatus may be sold as a single unit or kit. The case not onlyfunctions as a carrier assembly for the dispensing apparatus, but mayalso function as a shipping container therefor or as a display case.

In one aspect of the invention, a fluid dispensing apparatus isdescribed which includes: at least one elongated cylinder; alongitudinally axial sliding valve in a hemispherical dome of eachcannister, the valve biased in a closed position; a cylinder actuatorbottom for each cannister, each cylinder actuator bottom having acentrally disposed cylinder actuator bottom aperture disposed thereinand an outer cylindrical collar, the collar having at least two firstdetents positioned about the exterior of the collar, each detentconnected to a descending peripheral slot which extends about a portionof the periphery of the collar and which terminates toward a base of thecylinder actuator bottom; a cylinder actuator top for each cannister,each having a centrally disposed cylinder actuator top aperture disposedtherein, the cylinder actuator top aperture in sliding engagement withthe cylinder actuator bottom aperture, the cylinder actuator top havingat least two resiliently movable fingers, each finger having aprojection extending into an interior of the cylinder actuator top, thefinger projection in initial axial mating engagement with the at leasttwo first detents and subsequent sliding engagement with the descendingperipheral slot of each detent by rotational movement of the cylinderactuator top, the rotational movement effecting downward pressure on thevalve of each cannister to position the valve in an open position; thefluid dispensing apparatus having an elongated housing: the housinghaving a rear and a front and a removable nozzle connector; at least onedeformable plastic hose in leak-proof communication with the valve ofeach cannister at one end and in leak-proof communication with a rearinlet of the removable nozzle connector for a nozzle at an opposed end;the nozzle connector comprising: a means for removable mating engagementwith a front of the elongated housing of the fluid dispensing apparatusand a mating means at a rear end of the nozzle connector; a means forremovable mating engagement with a tapered plastic tip at a front of thenozzle connector; and a removable hose crimping prevention means formaintaining the at least one plastic hose with less than fulldeformation during storage or shipment, the hose crimping preventionmeans positioned between the bottom of the housing and a pivotabletrigger of the spray apparatus.

Preferably, the plastic tip is a color-changing tip which comprises atleast one thermochromic material selected from the group consisting ofat least one liquid crystal or at least one leuco dye. Preferably, theat least one thermochromic material is at least two thermochromicmaterials disposed within the plastic tip or thereupon the at least oneplastic hose, each of said at least two thermochromic materialseffecting a color change at a different temperature. In yet anotheraspect, the at least one thermochromic material is at least threethermochromic materials disposed within the plastic tip or thereupon theat least one plastic hose, each of said at least three thermochromicmaterials effecting a color change at a different temperature.

The container for the above is of sufficient length and width to containthe at least one elongated cylinder, and often two elongated cylinders.The elongated cylinders may comprise an “A” and a “B” cylinder for atwo-component polyurethane foam, but may also include a single cylinderfor a one-component polyurethane foam or two cylinders, each having thesame or different composition for a one-component foam. Whilepolyurethane foams are the targeted application, the application is notlimited to foams or to polyurethane, but includes all pressurized fluiddispensing applications in which the cylinders either contain all of thereactants or some of the reactants, or even different reactantsdepending on the targeted end-use application.

In another aspect, the removable hose crimping prevention means is anelongated plastic insert having an extension at one end and the nozzleconnector is completely disengageable from the housing.

In another embodiment, the fluid dispensing kit includes: at least oneelongated cylinder; a longitudinally axial sliding valve in ahemispherical dome of each cannister, the valve biased in a closedposition; a cylinder actuator bottom for each cannister, each cylinderactuator bottom having a centrally disposed cylinder actuator bottomaperture disposed therein and an outer cylindrical collar, the collarhaving at least two first detents positioned about the exterior of thecollar, each detent connected to a descending peripheral slot whichextends about a portion of the periphery of the collar and whichterminates toward a base of the cylinder actuator bottom; a cylinderactuator top for each cannister, each having a centrally disposedcylinder actuator top aperture disposed therein, the cylinder actuatortop aperture in sliding engagement with the cylinder actuator bottomaperture, the cylinder actuator top having at least two resilientlymovable fingers, each finger having a projection extending into aninterior of the cylinder actuator top, the finger projection in initialaxial mating engagement with the at least two first detents andsubsequent sliding engagement with the descending peripheral slot ofeach detent by rotational movement of the cylinder actuator top, therotational movement effecting downward pressure on the valve of eachcannister to position the valve in an open position; the fluiddispensing apparatus comprising an elongated housing: the housing havinga rear and a front and a removable nozzle connector; at least onedeformable plastic hose in leak-proof communication with the valve ofeach cannister at one end and in leak-proof communication with a rearinlet of the removable nozzle connector for a nozzle at an opposed end;the nozzle connector comprising: a means for removable mating engagementwith a front of the elongated housing of the fluid dispensing apparatusand a mating means at a rear end of the nozzle connector; a means forremovable mating engagement with a tapered plastic tip at a front of thenozzle connector; a removable hose crimping prevention means formaintaining the at least one plastic hose with less than fulldeformation during storage or shipment, the hose crimping preventionmeans positioned between the bottom of the housing and a pivotabletrigger of the spray apparatus; the rectangular container with apivotable top into which is positioned the at least one elongatedcylinder, each having the longitudinally axial sliding valve in thehemispherical dome of each cannister, the cylinder actuator bottom, thecylinder actuator top, the fluid dispensing apparatus, and the removablehose crimping prevention means, at least a portion of which extendsthrough a side wall of the container.

The kit preferably includes at least one plastic tip which is acolor-changing tip.

Another aspect of the invention includes a hemispherical cylinder valveopening device which comprises: a cylinder actuator bottom for eachcannister, each having a centrally disposed cylinder actuator bottomaperture disposed therein and an outer cylindrical collar, the collarhaving at least two first detents positioned about the exterior of thecollar, each detent connected to a descending peripheral slot whichextends about a portion of the periphery of the collar; and a cylinderactuator top for each cannister, each having a centrally disposedcylinder actuator top aperture disposed therein, the cylinder actuatortop aperture in sliding engagement with the cylinder actuator bottomaperture, the cylinder actuator top having at least two resilientlymovable fingers, each finger having a projection extending into aninterior of the cylinder actuator top, the finger projection in initialaxial mating engagement with the first detent and subsequent slidingengagement with the descending peripheral slot and second detent byrotational movement of the cylinder actuator top, the rotationalmovement effecting downward pressure on the valve of each cannister toposition the valve in an open position.

The cylinder valve opening device will include a plurality of detents atvarious locations. In one aspect, a second detent is adjacent the firstdetent and a third detent at an end of the descending peripheral slot ofthe cylinder actuator bottom. The cylinder valve opening device willhave a plurality of ribs which extend peripherally from the centrallydisposed cylinder actuator bottom aperture and extend to the outercylindrical collar.

In an aspect of the invention, the cylinder actuator bottom for eachcannister has at least three detents positioned about the exterior ofthe collar, each detent connected to the descending peripheral slotwhich extends about a portion of the periphery of the collar; and acylinder actuator top for each cannister wherein each cylinder actuatortop has at least three resiliently movable fingers for insertion intoeach of the at least three detents in the cylinder actuator bottom.

The invention includes a spray wand which comprises: an essentiallyhollow elongated housing having a rear and a front; a pivotable triggerbiased in a forward direction; at least one deformable plastic hose inleak-proof communication with a valve of at least one supply cannisterat one end and in leak-proof communication with a rear inlet of aremovable nozzle connector for a nozzle at an opposed end; the nozzleconnector including: a means for removable mating engagement with thefront of the housing at a rear end of the nozzle connector; a means forremovable mating engagement with a tapered wand tip at a front of thenozzle connector; a removable hose crimping prevention means formaintaining the at least one plastic hose with less than fulldeformation during storage or shipment, the hose crimping preventionmeans positioned between the bottom of the housing and the pivotabletrigger of the spray wand, thereby preventing full forward extensionwhile the crimping prevention means is positioned therein.

In one version of the above, the spray wand means for removable matingengagement with the front of the housing at a rear end of the nozzleconnector is a mating semicircular female slot with a semicircularhousing. The spray wand means for removable mating engagement with atapered wand tip at the front of the nozzle connector is a mating pairof wings at a rear of the tapered wand tip with a pair of receivingslots at the front of the nozzle connector.

The fluid dispensing device will further include a means to preventcrimping of a hose within a dispensing wand comprising: an elongatedessentially hollow housing having a front and a back, the housingcontaining at least one deformable plastic tube in fluid connection witha pressurized source of reactants and a dispensing nozzle at the front;a pivotable forwardly-biased trigger attached to a bottom of the hollowhousing, the trigger having a forward-extending projection, the triggercontrolling a flow of fluid within the at least one deformable plastictube by the interaction of a fixed v-shaped projection from the top ofthe housing and a movable projection at a top of the trigger; a crimpingminimization means positioned between the bottom of the hollow housingand a top surface of the forward-extending projection, the crimpingminimization means prohibiting full forward extension of the trigger,the crimping minimization means maintaining at least a partial openingof the at least one plastic tube.

The crimping minimization means is a plastic insert, the insert having abody and a forward-extending projection, a length of theforward-extending projection being sufficient to extend through a sidewall of a rectangular container housing the device during shipment.

Additionally, the invention encompasses a kit comprising: an enclosedcontainer having a lid, the lid being pivotable or removable from thecontainer; at least one elongated pressurized cylinder within thecontainer, the cylinder having a hemispherical domed top and a valve; atleast one pair of mating cylinder actuators, the pair of cylinderactuators depressing the cylinder valve by rotational movement of atleast one actuator; a deformable plastic hose positioned to eachcylinder valve at one end and positioned to a rear of a removable wandassembly at an opposed end; the wand assembly removably engaging a frontof a housing of the wand assembly; the wand assembly further comprisinga pivotable trigger for flow control, the trigger biased in a closedforward position; and the wand assembly stored and shipped with thetrigger in at least a partial open position by the insertion of ananti-crimping hose deformation means positioned between the trigger anda bottom of the housing of the wand assembly.

These and other objects of the present invention will become morereadily apparent from a reading of the following detailed descriptiontaken in conjunction with the accompanying drawings wherein likereference numerals indicate the parts and appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may take physical form in certain parts and arrangementsof parts, a preferred embodiment of which will be described in detail inthe specification and illustrated in the accompanying drawings whichform a part hereof, and wherein:

FIG. 1 is an assembly view of the two-component system of the Prior Artshowing two aerosol cans positioned within a two part top housing plateand a bottom canister positioning plate;

FIG. 2 is a perspective view of the bottom side of the canisterpositioning plate of the Prior Art;

FIG. 3 is an assembly view of a valve depressor for one aerosoldispensing valve of the Prior Art;

FIG. 4 is an assembly view of the shut-off valve housing within thedispensing nozzle of the Prior Art;

FIG. 5 is an assembly view of a push button dispensing nozzle of thePrior Art;

FIG. 6 is a side elevational view in partial cross-section showing thepush button dispensing nozzle of the Prior Art in the closed position;

FIG. 7 is an enlarged side elevational view in partial cross-sectionshowing the push button dispensing nozzle of the Prior Art in a closedposition with supplemental outwardly biased spring;

FIG. 8A is a top perspective view of a cylinder actuator bottom;

FIG. 8B is a top perspective view of a mating and insertable cylinderactuator top;

FIG. 9 is a partial cut-away view of a mating cylinder actuator bottomand top affixed to the hemispherical collar of a cylinder;

FIG. 10 is a perspective view of the cylinder actuator top in the firstdetent position of the cylinder actuator bottom;

FIG. 11 is a top perspective view of two cannisters inside a containerwith actuator tops and bottoms affixed to the cannisters;

FIG. 12 is a top perspective view of the spray gun positioned within thetop of an inner flap of the container, the trigger illustrated in apartially open position to prevent hose crimping during storage andshipment;

FIG. 13 is a side perspective view of the spray gun removed from thecontainer;

FIG. 14 is perspective view of the spray gun tip removed from the frontof the spray gun housing;

FIG. 15 is an enlarged view of the tip of the spray gun removed from thefront of the spray gun housing;

FIG. 16 side view in partial cut-away of the spray gun withanti-crimping means positioned between the trigger and bottom of thehousing;

FIG. 17 is an enlarged view of the pinching flow control mechanism;

FIG. 18 a side view in partial cut-away of the pinching controlmechanism of FIG. 17;

FIG. 19 is a view of the spray gun in use by an operator with spray tipslightly removed from the spray gun housing;

FIG. 20 is a top perspective view of FIG. 16 illustrating a portion ofthe safety protruding from one side of the container;

FIG. 21 is a side perspective view of FIG. 20;

FIG. 22 is a side perspective view of FIG. 21 with the top lid closed;

FIG. 23 is a perspective view of a cardboard insert used to keep thecannisters in-place;

FIG. 24 is a perspective view of FIG. 23 illustrating a glue pattern;

FIG. 25 is a perspective view of the cardboard insert with cannistersaffixed to the insert;

FIG. 26 is a perspective view of the cardboard insert with cannistersaffixed to the insert and the combination inserted into the shippingcontainer; and

FIG. 27 is a perspective view of the spray gun when employed using aone-component foam.

DETAILED DESCRIPTION

Unless the context clearly indicates otherwise: the word “and” indicatesthe conjunctive; the word “or” indicates the disjunctive; when thearticle is phrased in the disjunctive, followed by the words “or both”or “combinations thereof” both the conjunctive and disjunctive areintended.

As used in this application, the term “approximately” is within 10% ofthe stated value, except where noted. The terms “cylinder” and“cannister” are used interchangeably and synonymously.

Referring now to the drawings wherein the showings are for purposes ofillustrating the preferred embodiment of the invention only and not forpurposes of limiting the same, the Figures preferably show atwo-component portable polyurethane foam apparatus, optionally forinclusion in kit form. It is to be understood that the words “container”or “box” or case or kit are, for purposes of this description, identicaland are used interchangeably throughout the specification in describingthe combination of the foam dispensing system plus carrying case. Whilethe preferred application is a two-component polyurethane foam, there isno need to limit the invention to the same. It is envisioned that bothone-component and two-component fluid-dispensing devices are within thescope of this invention.

The portable two-component polyurethane foam kit includes two cylinders,typically an “A” cylinder, which contains a polymeric isocyanate and a“B” cylinder, which contains a polyol amine or resin. Formulationswithin each cylinder can vary significantly depending on theapplication. For example, adhesive applications produce a polyurethanefoam which has very little, if any, “foam” while insulation applicationsuse a formulation which produces a significant rise in the foam.Usually, portable, hand carried two-component polyurethane foam kitsdispense the chemicals from the dispensing apparatus as a “froth” havinga consistency or texture similar to that dispensed from an aerosol canof shaving cream. All such variations in the formulations ofpolyurethane and whether the chemicals are dispensed as a spray or frothare included within the scope of the present invention so long as theformulations are supplied in a portable, hand-carry form.

As illustrated in the Prior Art of FIGS. 1-7, a two-component fluid(e.g., polyurethane foam) dispensing holder assembly 10 is shownillustrating an A aerosol component and a B aerosol component. Thedispensing holder assembly 10 has an elongated oval canister positioningplate 12 having a top 14 and a bottom 18 side as well as an elongatedoval two component top housing assembly 4 having an upper housing 6 anda lower housing 8. Canister positioning plate 12 has a pair of raisedcircular ridges 16 on the top side 14 of the canister positioning platewhich are dimensioned for frictional engagement with either of thecircular aerosol can bottoms 24. Optionally, the raised circular ridgeswill have an inwardly facing notch (not shown) at a bottom thereof formating engagement with the peripherally extending canister lip whenfully inserted into canister positioning plate 12. Optionally a pair ofsupporting ribs 22 connect each raised circular ridge at a peripheralpoint thereupon. For ease of use in a multilingual environment, bottomside 18 of canister positioning plate 12 has a pair of hands 20imprinted or molded thereunto to illustrate the location of anend-user's hands to effect longitudinal axial actuating movement of thevalves positioned upon aerosol canisters A and B for the aerosolcomponents which make up the two-component polyurethane foam. Uponlongitudinal axial compression, the aerosol system is transformed fromits inactive state into an active state ready-for-use due tocorresponding longitudinal axial compressive movement of the valvespositioned at the top of each aerosol can.

Bottom housing 8 of the two-component top housing assembly 4 will havean elongated bottom side 28 and a pair of openings 39 for insertion ofthe top (valve side) of canisters A and B through bottom side 30 oflower housing 8 with securing frictional engagement with a circularridge on each dome-shaped circular top 26 of aerosol cans A and B aswell as two pairs of resilient flexible upwardly-directioned clips 40(inner), 50 (outer). Outer clips 50 have a detent 43 for engagement withinwardly facing hook member 45 of downwardly facing latch member 44which when engaged with detent 43, secure the top 6 with elongatedbottom side 36 and bottom 8 housings of two component top housingassembly 4 together at a predefined spaced apart distance when thedispensing system is in its inactivated state. When transitioning fromthe inactive to the active state, hook 45 of latch member 44 isdisengaged from detent 43 by inward compressive movement of outer clips50 coupled with further longitudinal axial compression. Complete aerosolactivation via aerosol valve depression is achieved when matingengagement is effected between protruding lips 41 on inner clips 40 withlowered top surface 38 after penetration through a pair of receivingapertures 49 disposed on opposed ends of lowered surface 38 and inwardlydisposed oval ridge 32 of bottom housing 8 moves via sliding engagementtoward the top of raised portion 34. A pair of indentations 2 aredisposed within oval ridge 32 and positioned in proximity to ribbed exitport 53 positioned at the top of each outlet for each aerosol can foregress of a flexible plastic tube 52, 54 affixed to each aerosoldispensing valve 46 positioned on top of each valve stem of each aerosolcylinder.

As illustrated in FIG. 3, each aerosol dispensing valve 46 has anapertured bottom dimensioned for frictional engagement with an outerperiphery of a valve stem of the aerosol can and a ribbed exit port 53for affixing a plastic hose 52, 54 thereto via securing rings 51 fortransporting the contents of either aerosol can A or B to a dispensingnozzle as illustrated in FIGS. 4-5, by egress of said tubing throughindentations 2 of oval ridge 32 and cut-out portions 47 of raisedportion 34 of upper housing 6. Each tube enters an upper 92 and lower 94finned rear end 72 of the dispenser 100 through a pair of ribbed inletports 64 and secured by a pair of securing rings 63 for ingress of fluidinto chamber 56 having a vertically oriented axial bore 55 disposedtherethrough (see FIG. 4), a pair of ribbed inlet ports 64 and oneoutlet bore 67 as illustrated in FIGS. 5-7. Each aerosol dispensingvalve 46 is securedly fastened to raised portion 34 by retaining clips(not shown) extending downwardly from the raised portion and whichengage a peripheral edge of the dispensing valve.

Dispenser 100 is comprised of a finned rear segment 72, a chamber 56, acentrally apertured 88 front nozzle 70 having an exit bore 90, an upperretaining assembly 62 and a push-bottom 58 actuator. Front nozzle 70sealed within the dispenser by frictional or rotational screw-likeengagement of rearwardly protruding centrally apertured nozzle inlet 66with chamber exit bore 67 within chamber 56. In its fully insertedposition, laterally and peripherally extending shelf 68 of nozzle 70abuts front shelf 74 of finned rear segment 72 and front shelf 80 ofupper retaining assembly 62. Disposed within a forward compartment ofrear segment 72 is chamber 56 held in place via insertion of at leastone laterally extending projection into a mating recess in the forwardcompartment. Push-button 58 actuator is positioned and retained withinthe foam dispenser by laterally extending shelves or wings 78 which abutthe apertures overlapping top surface of upper retaining assembly 62 andretaining clips 104. Push-button valve 58 is biased in its closedposition, i.e., laterally extending apertures 84 within circularprojections 82 are not in fluid alignment with either the centrallydisposed inlet bores 102 within ribbed inlet tubes 64 or chamber exitbore 67. Resilient upward biasing is effected by the incorporation ofextension piece 96 in contact with a bottom split wall 98 of thedispensing nozzle defining movable resiliently flexible flap 76 of rearsegment 72. Only upon positive downward engagement by a user of thenozzle will the horizontal laterally extending apertures 84 with raisedlips about a periphery at both ends of the apertures, move intoessentially leak-proof fluid alignment with inlet bores 102 and chamberexit bore 67 and nozzle entrance bore 88 egressing through nozzle tip90. In an optional embodiment the nozzle will further incorporate asecondary biasing means, e.g., a spring 99 for insuring that push button58 remains in a closed position unless purposefully depressed andactivated by an end user.

As an additional safety feature preventing against accidental orpremature activation of the canisters through depression of the valves,a safety insert 48 may be incorporated into the assembly. This inserthas a pair of legs 42 with extensions 59 which are insertable intoreceiving apertures 49 positioned within lowered surface 38. With thesafety inserted, it is not possible for the inner pair of clips 40 topenetrate through apertures 49 for locking engagement with loweredsurface 38.

The Prior Art however, has several limitations which are addressed inthe present invention discussed hereinbelow.

While the dispensing assembly is preferably used to dispensepolyurethane foams, any pressurized fluid (gas, liquid, semi-solid orcombinations thereof) is capable of being dispensed. Additionally, theinvention is not limited to any one foam or polymer and additionally, isnot limited to two canister two-component “A” and “B” systems. When thefoam to be dispensed is a one-component system, the dispensing apparatuswill operate with two canisters, each containing the same or differentone-component compositions, and each canister positioned in thelocations identified for the A and B components previously. In analternative embodiment, the assembly will function with only onecanister, said canister positioned in either of the two locationsindicated previously, or positioned more centrally between thoselocations. Unlike the Prior Art identified in FIGS. 1-7, the presentinvention does not employ a combined two-component top housing assembly4 (as shown in FIG. 1) in which both canisters are activatedsimultaneously by user interaction. As illustrated in FIGS. 8(A) and8(B), the improved foam dispensing gun employs an independent multipledetent mating component approach to independent cylinder activation ofthe “A” and “B” cylinders. Cylinder actuator bottom 110 has a bottomwith a plurality of wings 112, a central aperture 114 and a plurality ofribs extending in a spoke-like manner from aperture 114 to outerperipheral collar 118. This outer collar has at least two, preferablythree detents 130 positioned on the exterior of the collar. Greater andlesser numbers of detents are envisioned within the scope of thisinvention. Each uppermost first detent 130 is preferably longitudinallyaxially connected to a second detent 131, and descending spiralperipheral slot 132 which extends about a portion of the periphery ofthe collar and which terminates in third detent 134. Cylinder actuatortop 120 has at least two, preferably three resiliently movable fingers,but in all cases, the number of first detents will equal the number ofresiliently movable fingers. Each finger will have a projection 126projecting into an interior of the actuator top. Cylinder actuatorbottom 110 interfaces with cylinder actuator top 120 by initial axialmating engagement of first detent 130 with resiliently movable finger124 and projection 126 of cylinder actuator top 120 by positioning ofthe same in overlapping relationship. Cylinder bottom 110 has a centralaperture 114 into which is positioned cylinder top aperture 128, thecombined opening of which is inserted valve stem 136 of cylinder “A” orcylinder “B”, slidingly positioned within cylinder collar 140. Securedlyattached upon valve stem 136 in a leak-proof manner, is valve stem inlethose insert 138. When resiliently movable projection 126 is in its firstdetent position (storage/shipping position) 130, the cylinders arenon-operative as valve stem 136 and valve stem inlet hose insert 138remain in a non-engaged (or non-pressurized) position with thepressurized cylinder contents. By employing downward axial movement,resiliently movable projection 126 is directed from first detent 130into second detent position 131 (see FIG. 10). Continued rotationalmovement about the longitudinal axis of either cylinder, i.e., alongdescending peripheral slot 132, cylinder actuator top 120 is forceddownward in a longitudinally axial direction. Upon resiliently movableprojection 126 reaching the end of descending peripheral slot 132, theprojection reaches third detent 134 with concurrent activation of thepressurized contents of either the “A” or “B” cylinders as the downwardmovement of cylinder actuator top 120 coaxially exerts downward movementof the cylinder valve stem 136 which pressurizes the delivery hoses 142(shown in FIG. 11) which are affixed to valve stem inlet hose insert138. While three detent positions have been described above, only thefirst detent is a physical depression in the classical sense of adetent. The second detent position is held in place by the bottom of thefirst detent coupled with a downward spiral of path 132. After completerotation, the third detent position is held in place by the end walls ofpath 132. In a variation of the above depiction illustrated in FIG. 10,cylinder actuation may be effected by only employing a pair of detentsin longitudinal axial relationship to each other. First detent position130 and second detent position 131 can be in spaced apart longitudinallyaxial relationship to each other with second detent position 131 beingseparated by a sufficient distance so as to activate the pressurizedcontents of either the “A” or “B” cylinders by depression of valve stem136 and valve stem inlet hose insert 138. In essence, the axiallongitudinal compression which is illustrated by third detent position134 is achievable by simply increasing the spacing between first detent130 and second detent position 131.

As illustrated in FIG. 11, cylinders (or synonymously cannisters) “A”and “B” are positioned inside a container, typically a cardboard box 160having an interior 146 and at least one lid, preferably two lids, aninner lid 144 and an outer lid 162. Inner lid has an aperture 148through which hoses 142 project. Inner lid 144 additionally has aplurality of storage affixing locations, illustrated by hose-crimpingprevention means 150 in combination with aperture 152 and nozzle 154storage via aperture 156 and optionally aperture 158 for nozzle 176(illustrated in FIG. 20). As better illustrated in FIG. 12, hoses 142project through inner lid (or flap) 144 and enter the rear portion ofhousing 164 of foam spray gun 200. The gun has a longitudinallyextending housing 164 and a handle projecting in a generally transversedirection to the longitudinal axis of the housing. Forward of the handleis trigger 168 (shown partially retracted in the figure by hose-crimpingprevention means 150, which is positioned between trigger extension 170and a bottom surface of housing 164. Trigger 168 is biased in a closedposition by spring 172. Positioned within the inner flap is nozzle tip154 and optional second tip 176. Either tip may be secured to the frontof housing 164 by tip connector 178, which permits removable insertionof the dispensing assembly which is discussed in more detail below. FIG.13 illustrates spray gun 200 with hose-crimping prevention means 150removed as would occur in actual operation of the spray gun.

FIGS. 14-15 illustrate the unique ability of a user to easily extend thereach of spray gun 200 and its nozzle into hard-to-reach areas. In FIG.14, nozzle tip 176 is shown separated from the front of spray gunhousing 164. Nozzle tip 176 is positioned by insertion into nozzle tipholder 182 which is removably attached to the front of nozzle housing164 by the mating geometry of the front of the nozzle housing 180. Thefront of the housing has an essentially grooved semicircular surfaceinto which a mating semicircular surface projection 188 is inserted.While the groove of the front of nozzle housing 180 is illustrated assemicircular as is the mating semicircular surface projection 188, thereis no reason to limit the shape to semicircular. The shape could berectangular or “n”-shaped polygon. The key is that the surfaces matewith each other. Similarly, for various applications nozzles withdifferent degrees of angularity to the tip of the nozzle are useful inthis invention, each different type of angularity, providing a differentfoam spray pattern. Nozzles 176 are interchangeable through the matinggeometry of projecting wings of the rear of the nozzle tip andinwardly-facing mating slots 184 in nozzle holder 182. Nozzle hoses 142are affixed typically via friction insertion onto projecting cylindricalrods 190, typically having barbed gripping surfaces, better illustratedin FIG. 16, affixed to the rear of surface projection 188.

Another improvement over the Prior Art is illustrated in FIGS. 16-18.Flow control for spray gun 200 is achieved by fully opening and fullyclosing plastic hoses 142 by pinching fixed v-shaped edge 192,positioned across a top of the housing and pivotable and movable edge194 together. When trigger 168 is in its fully extended position, theedges are essentially adjacent each other as illustrated in FIG. 18 andwhen the trigger is in its fully contracted position, the edges are notin contacting engagement with plastic hoses 142 as illustrated in FIG.16. The value of this approach is that accidental premature use of spraygun 200 is prevented. However, there is shape retention memory inplastic hoses 142, which depending on the length of storage in theclosed position, may prevent full flow of the chemicals through plastichoses 142 when trigger 168 is in its fully retracted (or open) position.One solution to this problem is to ship the trigger in a partiallyclosed position or even in the fully open position. This was illustratedby plastic insert 150 in FIG. 12, but equivalently is illustrated as anelongated plastic insert 150 (see FIG. 16) affixed between the upperfinger rest 170 and the bottom of housing 164. Spray gun 200 ispreferably shipped with plastic insert extension 198 extending throughone side 146 of container 160 (better illustrated in FIGS. 20-21),thereby preventing the contents of either cannister from prematurelybeing accessed and the plastic hoses 142 from being deformed byimpacting edges 192, 194. Partial closing of the edges is illustrated inFIG. 17 and complete closure is illustrated in FIG. 18. As illustratedin FIGS. 20-21, the plastic insert extension 198 is positioned between acontainer side 146 of container 160 and an upper side flap 202 of thecontainer. The upper lid 206 is formed by the folding of opposed upperside flaps 202 and upper front flap 204 illustrated in FIG. 22.

In operation, the cylinders are upside-down as illustrated in FIG. 19with hoses 142 protruding through aperture 196. This allows essentiallycomplete utilization of the contents of the “A” and “B” cylinders (orjust one of the cylinders in the case of a one-component foamapplication) as well as permitting the operator to carry the carton 160for use at the intended site application. In light of the upside-downnature of the use of the product, a cardboard insert 210 is typicallyprovided to assist in holding the cylinders in place, as for example bylocations 208 for the cylinder bottoms and locations 220 for thecontacting side periphery of the cylinders as illustrated in FIG. 23.The application of a hot melt glue is illustrated in FIG. 24 by thepattern illustrated as 214 and as illustrated as 216, recognizing thatalternatives to a hot melt glue include, but are not limited to: foamtape, double-sided tape or even cut-outs matched to the geometry of thecylinders. Cardboard insert 212 is affixed within the container by theapplication of a hot melt adhesive, as illustrated in FIGS. 24-26,although many locations are equally applicable as are other attachmentmeans such as foam tape, double-sided tape or even cut-outs matched tothe geometry of the cylinders.

While the focus of the application has been directed so far to“two-component” foams, particularly two-component polyurethane sprayfoams, the invention is not limited to such. In fact, the invention isbroad enough to cover any pressurized fluid dispensing device. In fact,it is easily envisioned that one-component foams, particularlyone-component polyurethane foams are easily adaptable to the fluiddispensing technology described herein. The major change being that onlyone cannister is required, employing one plastic hose 142 as illustratedin FIG. 27. This presents the opportunity to have one cannister withinthe container, or to have two one-component cannisters, the secondcannister serving to allow the user to dispense more product by simplyswitching the single deformable plastic tubing from one cannister to theother. Alternatively, only one cannister may reside within thecontainer.

Spray gun 200 is usable by one person. In operation, the spray apparatusis activated by removal of the hose pinching minimization means (eithera foam insert or a plastic insert), followed by actuation of thecylinder contents by longitudinal axial movement of each cylinderactuation top from a first detent position to a second detent position,followed by independent rotation of each cylinder actuation top from thesecond detent position to a third detent position, the rotation of whichindependently depresses each cylinder valve. For use indifficult-to-reach areas, the operator has the flexibility of removingthe nozzle tip from the gun housing to extend the reach of the nozzletip and better and more easily complete the job.

At least one recurring quality issue facing the disposable polyurethanefoam kit industry is the inability of end-users to effectively assessthe core chemical temperature of the liquid and gas contents containedtherein. Two important functions are often negatively impacted:achievement of maximum foam kit yield on the job site, and properchemical cure of the “A” & “B” components.

Maximum yield is highly desired by purchasers of polyurethane foam kitproducts. If the chemicals are too cold for optimum use, the “B”-sideviscosity increases, which in turn distorts the 1:1 ratio (by weight)required for proper yield. Lower-than-advertised yields carrysignificant economical consequences for the contractor.

Proper chemical cure (on-ratio ˜1:1) is also critical to achievingmaximum physical properties. It ensures that the cured foam meetsbuilding code specifications, e.g. fire ratings. In addition, acomplete, on-ratio cure is critical for the health and safety of foamkit operators and building occupants. Again, cold chemical temperatures(below recommended) can create off-ratio foam, with the resultingincomplete chemical cure. While an on-ratio of ˜1:1 is often targeted,it is recognized that kits could use different ratios by using differentformulas or by using different pressures, thereby permitting differentcompositions as needed for the targeted end-use application.

At least one important variable impacting the above issues is the corechemical temperature of the liquid/gas contents of the foam kit. Thecore chemical temperature of a kit before use must meet themanufacturer's recommended temperature, usually ˜75° F.-85° F., in orderto meet the objectives of maximum yield and proper (complete) chemicalcure. However, end-users typically do not condition the kits long enoughat the recommended temperature. For example, kits stored in anunconditioned warehouse or insulation truck in the winter months mayhave a core chemical temperature of only ˜40° F. If dispensed withoutbeing conditioned for a sufficient amount of time, the result is foam ofvery poor physical quality and appearance. Also, improper chemical curewill most likely occur (unbalanced ratio of “A” to “B” chemical, whichis typically 1:1 by weight). This “off-ratio” foam becomes a liabilityfor the reasons mentioned above. It can take up to 48 hours to conditioncylinders to the recommended chemical temperature, a recommendationoften ignored by end-users.

The industry has long searched for an effective, economical way to allowend-users to gauge the core chemical temperature of a kit with areasonable degree of qualitative accuracy before applying the foam. Thisinvention utilizes thermochromism in both the nozzle and the hosesassociated with the “A” and “B” chemicals to determine when thetemperature of the chemicals falls within the acceptable use range,based upon the color change of the nozzle or hose due to a change intemperature of the flowing chemical.

The ability to determine the chemical temperature as it exits the “A”and “B” cylinders through respective “A” and “B” flexible plastic hosesor the ability to determine the chemical temperature as it enters and/orexits the disposable nozzle is effected either by having a thermochromicmaterial contained within the plastic used to mold disposable nozzle orto fabricate the flexible plastic hoses. Still another approach involvesaffixing a label either permanently using a permanent adhesive ornon-permanently, using a pressure-sensitive adhesive (the labeloptionally having thermochromic text or thermochromic graphic materialprinted thereupon) which changes in one instance from colored (below therecommended use temperature), to colorless or a different color when thechemicals have transferred a sufficient amount of heat to the nozzle orlabel.

Thermochromism is typically implemented via one of two commonapproaches: liquid crystals and leuco dyes. Liquid crystals are used inprecision applications, as their responses can be engineered to accuratetemperatures, but their color range is limited by their principle ofoperation. Leuco dyes allow wider range of colors to be used, but theirresponse temperatures are more difficult to set with accuracy.

Some liquid crystals are capable of displaying different colors atdifferent temperatures. This change is dependent on selective reflectionof certain wavelengths by the crystalline structure of the material, asit changes between the low-temperature crystalline phase, throughanisotropic chiral or twisted nematic phase, to the high-temperatureisotropic liquid phase. Only the nematic mesophase has thermochromicproperties. This restricts the effective temperature range of thematerial.

The twisted nematic phase has the molecules oriented in layers withregularly changing orientation, which gives them periodic spacing. Thelight passing through the crystal undergoes Bragg diffraction on theselayers, and the wavelength with the greatest constructive interferenceis reflected back, which is perceived as a spectral color. A change inthe crystal temperature can result in a change of spacing between thelayers and therefore in the reflected wavelength. The color of thethermochromic liquid crystal can therefore continuously range fromnon-reflective (black) through the spectral colors to black again,depending on the temperature. Typically, the high temperature state willreflect blue-violet, while the low-temperature state will reflectred-orange. Since blue is a shorter wavelength than red, this indicatesthat the distance of layer spacing is reduced by heating through theliquid-crystal state.

Some such materials are cholesteryl nonanoate or cyanobiphenyls. Liquidcrystals used in dyes and inks often come microencapsulated, in the formof suspension. Liquid crystals are used in applications where the colorchange has to be accurately defined.

Thermochromic dyes are based on mixtures of leuco dyes with suitableother chemicals, displaying a color change (usually between thecolorless leuco form and the colored form) in dependence on temperature.The dyes are rarely applied on materials directly; they are usually inthe form of microcapsules with the mixture sealed inside. Anillustrative example would include microcapsules with crystal violetlactone, weak acid, and a dissociable salt dissolved in dodecanol; whenthe solvent is solid, the dye exists in its lactone leuco form, whilewhen the solvent melts, the salt dissociates, the pH inside themicrocapsule lowers, the dye becomes protonated, its lactone ring opens,and its absorption spectrum shifts drastically, therefore it becomesdeeply violet. In this case the apparent thermochromism is in facthalochromism.

The dyes most commonly used are spirolactones, fluorans, spiropyrans,and fulgides. The weak acids include bisphenol A, parabens,1,2,3-triazole derivates, and 4-hydroxycoumarin and act as protondonors, changing the dye molecule between its leuco form and itsprotonated colored form; stronger acids would make the changeirreversible.

Leuco dyes have less accurate temperature response than liquid crystals.They are suitable for general indicators of approximate temperature.They are usually used in combination with some other pigment, producinga color change between the color of the base pigment and the color ofthe pigment combined with the color of the non-leuco form of the leucodye. Organic leuco dyes are available for temperature ranges betweenabout 23° F. (−5° C.) and about 140° F. (60° C.), in wide range ofcolors. The color change usually happens in about a 5.4° F. (3° C.)interval.

The size of the microcapsules typically ranges between 3-5 μm (over 10times larger than regular pigment particles), which requires someadjustments to printing and manufacturing processes.

Thermochromic paints use liquid crystals or leuco dye technology. Afterabsorbing a certain amount of light or heat, the crystalline ormolecular structure of the pigment reversibly changes in such a way thatit absorbs and emits light at a different wavelength than at lowertemperatures.

The thermochromic dyes contained either within or affixed upon eitherthe disposable nozzle or hoses may be configured to change the color ofthe composition in various ways. For example, in one embodiment, oncethe composition reaches a selected temperature, the composition maychange from a base color to a white color or a clear color. In anotherembodiment, a pigment or dye that does not change color based ontemperature may be present for providing a base color. The thermochromicdyes, on the other hand, can be included in order to change thecomposition from the base color to at least one other color.

In one particular embodiment, the plurality of thermochromic dyes areconfigured to cause the cleansing composition to change color over atemperature range of at least about 3° C., such as at least about 5° C.,once the composition is heated to a selected temperature. For example,multiple thermochromic dyes may be present within the cleansingcomposition so that the dyes change color as the composition graduallyincreases in temperature. For instance, in one embodiment, a firstthermochromic dye may be present that changes color at a temperature offrom about 23° C. to about 28° C. and a second thermochromic dye may bepresent that changes color at a temperature of from about 27° C. toabout 32° C. If desired, a third thermochromic dye may also be presentthat changes color at a temperature of from about 31° C. to about 36° C.In this manner, the cleansing composition changes color at the selectedtemperature and then continues to change color in a stepwise manner asthe temperature of the composition continues to increase. It should beunderstood that the above temperature ranges are for exemplary andillustrative purposes only.

Any thermochromic substance that undergoes a color change at the desiredtemperature may generally be employed in the present disclosure. Forexample, liquid crystals may be employed as a thermochromic substance insome embodiments. The wavelength of light (“color”) reflected by liquidcrystals depends in part on the pitch of the helical structure of theliquid crystal molecules. Because the length of this pitch varies withtemperature, the color of the liquid crystals is also a function oftemperature. One particular type of liquid crystal that may be used inthe present disclosure is a liquid crystal cholesterol derivative.Exemplary liquid crystal cholesterol derivatives may include alkanoicand aralkanoic acid esters of cholesterol, alkyl esters of cholesterolcarbonate, cholesterol chloride, cholesterol bromide, cholesterolacetate, cholesterol oleate, cholesterol caprylate, cholesterololeyl-carbonate, and so forth. Other suitable liquid crystalcompositions are possible and contemplated within the scope of theinvention.

In addition to liquid crystals, another suitable thermochromic substancethat may be employed in the present disclosure is a composition thatincludes a proton accepting chromogen (“Lewis base”) and a solvent. Themelting point of the solvent controls the temperature at which thechromogen will change color. More specifically, at a temperature belowthe melting point of the solvent, the chromogen generally possesses afirst color (e.g., red). When the solvent is heated to its meltingtemperature, the chromogen may become protonated or deprotonated,thereby resulting in a shift of the absorption maxima. The nature of thecolor change depends on a variety of factors, including the type ofproton-accepting chromogen utilized and the presence of any additionaltemperature-insensitive chromogens. Regardless, the color change istypically reversible.

Although not required, the proton-accepting chromogen is typically anorganic dye, such as a leuco dye. In solution, the protonated form ofthe leuco dye predominates at acidic pH levels (e.g., pH of about 4 orless). When the solution is made more alkaline through deprotonation,however, a color change occurs. Of course, the position of thisequilibrium may be shifted with temperature when other components arepresent. Suitable and non-limiting examples of leuco dyes for use in thepresent disclosure may include, for instance, phthalides; phthalanes;substituted phthalides or phthalanes, such as triphenylmethanephthalides, triphenylmethanes, or diphenylmethanes; acyl-leucomethyleneblue compounds; fluoranes; indolylphthalides, spiropyranes; cumarins;and so forth. Exemplary fluoranes include, for instance,3,3′-dimethoxyfluorane, 3,6-dimethoxyfluorane, 3,6-di-butoxyfluorane,3-chloro-6-phenylamino-flourane, 3-diethylamino-6-dimethylfluorane,3-diethylamino-6-methyl-7-chlorofluorane, and3-diethyl-7,8-benzofluorane,3,3′-bis-(p-dimethyl-aminophenyl)-7-phenylaminofluorane,3-diethylamino-6-methyl-7-phenylamino-fluorane,3-diethylamino-7-phenyl-aminofluorane, and2-anilino-3-methyl-6-diethylamino-fluorane. Likewise, exemplaryphthalides include 3,3′,3″-tris(p-dimethylamino-phenyl)phthalide,3,3′-bis(p-dimethyl-aminophenyl)phthalide,3,3-bis(p-diethylamino-phenyl)-6-dimethylamino-phthalide,3-(4-diethylaminophenyl)-3-(1-ethyl-2-methylindol-3-yl)phthalide, and3-(4-diethylamino-2-methyl)phenyl-3-(1,2-dimethylindol-3-yl)phthalide.

Although any solvent for the thermochromic dye may generally be employedin the present disclosure, it is typically desired that the solvent havea low volatility. For example, the solvent may have a boiling point ofabout 150° C. or higher, and in some embodiments, from about 170° C. to280° C. Likewise, the melting temperature of the solvent is alsotypically from about 25° C. to about 40° C., and in some embodiments,from about 30° C. to about 37° C. Examples of suitable solvents mayinclude saturated or unsaturated alcohols containing about 6 to 30carbon atoms, such as octyl alcohol, dodecyl alcohol, lauryl alcohol,cetyl alcohol, myristyl alcohol, stearyl alcohol, behenyl alcohol,geraniol, etc.; esters of saturated or unsaturated alcohols containingabout 6 to 30 carbon atoms, such as butyl stearate, methyl stearate,lauryl laurate, lauryl stearate, stearyl laurate, methyl myristate,decyl myristate, lauryl myristate, butyl stearate, lauryl palmitate,decyl palmitate, palmitic acid glyceride, etc.; azomethines, such asbenzylideneaniline, benzylidenelaurylamide, o-methoxybenzylidenelaurylamine, benzylidene p-toluidine, p-cumylbenzylidene, etc.; amides,such as acetamide, stearamide, etc.; and so forth.

The thermochromic composition may also include a proton-donating agent(also referred to as a “color developer”) to facilitate thereversibility of the color change. Such proton-donating agents mayinclude, for instance, phenols, azoles, organic acids, esters of organicacids, and salts of organic acids. Exemplary phenols may include phenylphenol, bisphenol A, cresol, resorcinol, chlorolucinol, b-naphthol,1,5-dihydroxynaphthalene, pyrocatechol, pyrogallol, trimer ofp-chlorophenol-formaldehyde condensate, etc. Exemplary azoles mayinclude benzotriaoles, such as 5-chlorobenzotriazole,4-laurylaminosulfobenzotriazole, 5-butylbenzotriazole, dibenzotriazole,2-oxybenzotriazole, 5-ethoxycarbonylbenzotriazole, etc.; imidazoles,such as oxybenzimidazole, etc.; tetrazoles; and so forth. Exemplaryorganic acids may include aromatic carboxylic acids, such as salicylicacid, methylenebissalicylic acid, resorcylic acid, gallic acid, benzoicacid, p-oxybenzoic acid, pyromellitic acid, b-naphthoic acid, tannicacid, toluic acid, trimellitic acid, phthalic acid, terephthalic acid,anthranilic acid, etc.; aliphatic carboxylic acids, such as stearicacid, 1,2-hydroxystearic acid, tartaric acid, citric acid, oxalic acid,lauric acid, etc.; and so forth. Exemplary esters may include alkylesters of aromatic carboxylic acids in which the alkyl moiety has 1 to 6carbon atoms, such as butyl gallate, ethyl p-hydroxybenzoate, methylsalicylate, etc.

The amount of the proton-accepting chromogen employed may generallyvary, but is typically from about 2 wt. % to about 20 wt. %, and in someembodiments, from about 5 to about 15 wt. % of the thermochromicsubstance. Likewise, the proton-donating agent may constitute from about5 to about 40 wt. %, and in some embodiments, from about 10 wt. % toabout 30 wt. % of the thermochromic substance. In addition, the solventmay constitute from about 50 wt. % to about 95 wt. %, and in someembodiments, from about 65 wt. % to about 85 wt. % of the thermochromiccomposition.

Regardless of the particular thermochromic substance employed, it may bemicroencapsulated to enhance the stability of the substance duringprocessing. For example, the thermochromic substance may be mixed with athermosetting resin according to any conventional method, such asinterfacial polymerization, in-situ polymerization, etc. Thethermosetting resin may include, for example, polyester resins,polyurethane resins, melamine resins, epoxy resins, diallyl phthalateresins, vinylester resins, and so forth. The resulting mixture may thenbe granulated and optionally coated with a hydrophilic macromolecularcompound, such as alginic acid and salts thereof, carrageenan, pectin,gelatin and the like, semisynthetic macromolecular compounds such asmethylcellulose, cationized starch, carboxymethylcellulose,carboxymethylated starch, vinyl polymers (e.g., polyvinyl alcohol),polyvinylpyrrolidone, polyacrylic acid, polyacrylamide, maleic acidcopolymers, and so forth. The resulting thermochromic microcapsulestypically have a size of from about 1 to about 50 micrometers, and insome embodiments, from about 3 to about 15 micrometers. Various othermicroencapsulation techniques may also be used.

Thermochromic dyes are commercially available from various sources. Inone embodiment, for instance, thermochromic dyes marketed by Chromadiccreations, Hamilton, Ontario and sold under the trade name SpectraBurstThermochromic Polypropylene.

The thermochromic dyes can be present in the composition in an amountsufficient to have a visual effect on the color of the composition. Theamount or concentration of the dyes can also be increased or decreaseddepending upon the desired intensity of any color. In general, thethermochromic dyes may be present in the composition in an amount fromabout 0.01% by weight to about 9% by weight, such as from about 0.1% byweight to about 3% by weight. For instance, in one particularembodiment, the thermochromic dyes may be present in an amount fromabout 0.3% to about 1.5% by weight.

As described above, thermochromic dyes typically change from a specificcolor to clear at a certain temperature, e.g., dark blue below 60° F. totransparent or translucent above 60° F. If desired, other pigments ordyes can be added to the composition in order to provide a backgroundcolor that remains constant independent of the temperature of thecomposition. By adding other pigments or dyes in combination with thethermochromic dyes to the composition, the thermochromic dyes canprovide a color change at certain temperatures rather than just a lossof color should the thermochromic dye become clear. For instance, anon-thermochromic pigment, such as a yellow pigment, may be used inconjunction with a plurality of thermochromic dyes, such as a red dyeand a blue dye. When all combined together, the cleansing compositionmay have a dark color. As the composition is increased in temperature,the red thermochromic dye may turn clear changing the color to a greenshade (a combination of yellow and blue). As the temperature furtherincreases, the blue thermochromic dye turns clear causing thecomposition to turn yellow.

It should be understood, that all different sorts of thermochromic dyesand non-thermochromic pigments and dyes may be combined in order toproduce a composition having a desired base color and one that undergoesdesired color changes. The color changes, for instance, can be somewhatdramatic and fanciful. For instance, in one embodiment, the compositionmay change from green to yellow to red.

In an alternative embodiment, however, the composition can containdifferent thermochromic dyes all having the same color. As thetemperature of the composition is increased, however, the shade orintensity of the color can change. For instance, the composition canchange from a vibrant blue to a light blue to a clear color.

In addition to the above, it should be understood that many alterationsand permutations are possible. Any of a variety of colors and shades canbe mixed in order to undergo color changes as a function of temperature.

It is to be appreciated that the interaction between the “A” and “B”components within the nozzle are complex. Further, the words “laminar”and “turbulent” are not used herein in their strict, classical sense butare used in a relative sense. Flow within the inlet chamber of thenozzle is believed to be relatively turbulent, the thermochromicmaterial changing color by measuring the temperature of either the highvolume flow of pressurized chemicals or high volume flow of synthesizedfroth foam or both egressing through said plastic nozzle to illustrateto the end-user of the spray gun if the pressurized chemicals andpropellant used to prepare the polyurethane foam or the polyurethanefroth are at a minimum temperature e.g., for proper chemical cure of the“A” and “B” chemicals, the propellant comprising a fluorocarbon and aninert gas in which the propellant enters into the nozzle as a liquidcomponent under the pressure of between approximately 80-120 psi andchanges to a gaseous state component during travel through the nozzleand egress therefrom into the environment with turbulent flow betweenthe liquid components, gaseous components and synthesized froth foam.

The propellant changes to a gaseous state component during travelthrough the nozzle and egress therefrom into the environment withturbulent flow between the liquid components, gaseous components andsynthesized froth foam.

It is quite surprising that a “froth” foam within a nozzle flowing underturbulent conditions would yield a color-change within the nozzle. Theheat transfer characteristics of a “froth” are not good. The “froth”would be in contact with the walls of the nozzle for a period of nolonger than a second or so (and for most two-component spray systemsusing 80-120 psi pressure in the hoses would result in a residence timewithin the nozzle of the spray gun of milliseconds at a typical flowrate. The very short contact time coupled with the large amount of“void” space, which is inherent in the definition of a “froth foam”makes it quite surprising that any type of indication of temperature ispossible in the nozzle of a spray foam gun. It is respectfully positedthat it is completely counter-intuitive to believe that any indicationof temperature is possible under these conditions. This is all the moreremarkable in that foam is used as insulation . . . and for that veryreason, its heat transfer characteristics are not good.

This invention has been described in detail with reference to specificembodiments thereof, including the respective best modes for carryingout each embodiment. It shall be understood that these illustrations areby way of example and not by way of limitation. The best mode forcarrying out the invention has been described for purposes ofillustrating the best mode known to the applicant at the time. Theexamples are illustrative only and not meant to limit the invention, asmeasured by the scope and merit of the claims. The invention has beendescribed with reference to preferred and alternate embodiments.Obviously, modifications and alterations will occur to others upon thereading and understanding of the specification. It is intended toinclude all such modifications and alterations insofar as they comewithin the scope of the appended claims or the equivalents thereof.

What is claimed is:
 1. A device to prevent crimping of a hose within adispensing wand comprising: an elongated essentially hollow housinghaving a front and a back, the housing containing at least onedeformable plastic tube in fluid connection with a pressurized source ofreactants and a dispensing nozzle at the front; a pivotableforwardly-biased trigger attached to a bottom of the hollow housing, thetrigger having a forward-extending projection, the trigger controlling aflow of fluid within the at least one deformable plastic tube by theinteraction of a fixed v-shaped projection from the top of the housingand a movable projection at a top of the trigger; and a crimpingminimization means positioned between the bottom of the hollow housingand a top surface of the forward-extending projection, the crimpingminimization means prohibiting full forward extension of the trigger,the crimping minimization means maintaining at least a partial openingof the at least one plastic tube.
 2. The device of claim 1 wherein thecrimping minimization means is a removable insert positioned between theforward-extending projection of the trigger and a bottom surface of thehollow housing.
 3. The device of claim 2 wherein the crimpingminimization means is an “X”-shaped insert.
 4. The device of claim 3wherein The insert is plastic.
 5. The device of claim 1 wherein thecrimping minimization means is a plastic insert, the insert having abody and a forward-extending projection, a length of theforward-extending projection being sufficient to extend through a sidewall of a rectangular container housing the device during shipment.
 6. Adevice to prevent crimping of a pair of hoses within a dispensing wandcomprising: an elongated essentially hollow housing having a front and aback, the housing containing a pair of deformable plastic tubes in fluidconnection with a pressurized source of reactants and a dispensingnozzle at the front; a pivotable forwardly-biased trigger attached to abottom of the hollow housing, the trigger having a forward-extendingprojection, the trigger controlling a flow of fluid within the pair ofdeformable plastic tubes by the interaction of a fixed v-shapedprojection from the top of the housing and a movable projection at a topof the trigger; and a crimping minimization means positioned between thebottom of the hollow housing and a top surface of the forward-extendingprojection, the crimping minimization means prohibiting full forwardextension of the trigger, the crimping minimization means maintaining atleast a partial opening of the pair of plastic tubes.
 7. The device ofclaim 6 wherein the crimping minimization means is a removable insertpositioned between the forward-extending projection of the trigger and abottom surface of the hollow housing.
 8. The device of claim 7 whereinthe crimping minimization means is an “X”-shaped insert.
 9. The deviceof claim 8 wherein the insert is plastic.
 10. The device of claim 6wherein the crimping minimization means is a plastic insert, the inserthaving a body and a forward-extending projection, a length of theforward-extending projection being sufficient to extend through a sidewall of a rectangular container housing the device during shipment.